DOVER - As the valley prepares for an influx of tourists and visitors in the coming weeks, North Branch Fire District officials are asking district users to conserve wastewater. The request comes amid a major upgrade to the district’s plant, which is experiencing weather-related delays that have affected the plant’s holding pond, therefore limiting effluent storage at the facility. On Tuesday, the Wilmington Selectboard approved an agreement with North Branch to accept some of North Branch’s wastewater at its facility, where it will be blended into Wilmington’s lagoons.